JP2001124246A - Grommet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grommet which does not easily pierce a hole even when the force or the external pressure is applied during the fitting or thereafter. SOLUTION: In the grommet 11 having an annular groove 3 extending toward a lower surface on an upper circumferential part and a boss part 5 on a center part, a plurality of notched grooves 12 are radially arranged on the upper circumferential part on the outer circumferential side of the annular groove 3 at equal spaces in the circumferential side, and integrated with the annular groove 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grommet used for closing a drain hole formed in a floor plate of, for example, a trunk room of an automobile.

[0002]

2. Description of the Related Art A grommet 1 of this kind in the related art is:
As shown in FIG. 9, an annular groove 3 extending toward the lower surface is formed in a circumferential portion of the upper surface, and a boss portion 5 is formed in a central portion.
A flange-shaped non-insertion portion 7 is formed on the outer side of the groove, and an engagement groove 6 for engaging the inner peripheral edge of the hole 10 (see FIG. 10) is formed below the non-insertion portion 7 in an annular shape. Is formed at the lower part of the hole, a blind hole 4 extending toward the upper surface is formed at the center of the lower surface, and the blind hole 4 has a large diameter at the opening end side and a small diameter toward the hole bottom side. It was made of a soft material such as plastic or rubber formed in a conical shape.

[0003] The grommet 1 is used for a car floor panel 9.
When the hole 10 formed in (steel plate) is closed with the grommet 1, as shown in FIG. 10A, the outer diameter of the non-insertion portion 7 is formed larger than the inner diameter of the hole 10 as a matter of course. However, the upper part is slightly larger than the inner diameter of the hole 10 and the lower part is the hole 1
By inserting the insertion portion 2 smaller than the inner diameter of 0 into the hole 10 and pushing the boss portion 5 with a stick or a fingertip to deform the annular groove 3, as shown in FIG. Hole 1
The inner peripheral edge of the hole 0 is fitted, and the non-insertion portion 7 is stopped at the upper portion of the hole 10 to prevent the non-insertion portion 7 from coming off.

[0004]

However, according to the conventional grommet 1, if the force P for pushing the grommet 1 is too strong, as shown in FIG. The diameter may be reduced by being entangled, and eventually the non-insertion portion 7 may pass through the hole 10. The peripheral portion of the non-insertion portion 7 has a cross-sectional shape that hangs slightly downward so as to generate an urging force that closely adheres to the floor plate 9 when mounted, and generates sealing performance, but its thickness is not very thick. Therefore, it tends to be easily deformed, so that it easily falls down to the annular groove 3 side, and the diameter of the non-insertion portion 7 is excessively reduced.

[0005] Even if the grommet 1 is normally mounted in the hole 10, if an external pressure is accidentally applied to the boss 5, the grommet 1 may penetrate the hole 10 as described above. Is clearly higher.

Since the function as a grommet is no longer achieved, it is necessary to be extremely careful in adjusting the pushing force P, and this requires skill and time, thus reducing the work efficiency.

Accordingly, the present invention provides a grommet that does not easily penetrate the hole even when a force or external pressure is applied during or after mounting.

[0008]

According to a first aspect of the present invention, there is provided a grommet in which a boss portion is formed at a center portion having an annular groove extending toward a lower surface in a circumferential portion of an upper surface. A plurality of notched grooves are formed integrally with the annular groove in the upper circumferential portion at equal circumferential intervals on the outer peripheral side of the annular groove.

Further, the boss portion is formed at the center portion with an annular groove extending toward the lower surface in the circumferential portion of the upper surface, and a flange-shaped non-insertion portion is provided outside the annular groove. A non-insertion part, an engagement groove for engaging the inner peripheral edge of the hole to be closed is formed in an annular shape, a truncated cone-shaped insertion part is formed below the engagement groove, and a lower surface center is formed. A blind hole extending toward the upper surface is formed in the part, and in the blind hole, the opening end side is formed in a conical shape having a large diameter and a small diameter toward the hole bottom side,
In addition, a plurality of notched grooves are formed integrally with the annular groove in the circumferential direction of the upper surface at equal circumferential intervals on the outer peripheral side of the annular groove.

According to a third aspect of the present invention, the cutout groove is a groove having a V-shaped cross-section, and as described in a fourth aspect, the insertion groove side of the engagement groove and / or Alternatively, the rib portion is formed in an annular shape on the non-insertion portion side, and the boss portion is shaped like a truncated cone as described in claim 5.

Therefore, when a hole such as a floor plate is closed by pushing the boss toward the lower surface as in the conventional case,
When an excessively strong pushing force is applied, the non-inserted portion crushes the cutout groove and the annular groove to reduce the diameter, and the solid portion between the cutout grooves contacts the boss, making them difficult to deform. Further, since the diameter of the non-insertion portion is prevented from being further reduced, the non-insertion portion does not penetrate through the hole to be closed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the grommet 11 according to the present invention has a non-insertion portion 7 formed in a flange shape at an upper portion, an insertion portion 2 formed at a lower portion, and an engagement groove portion 6 formed between them in an annular shape. A boss 5 is formed at the center of the upper surface, an annular groove 3 is formed around the boss 5, and a substantially conical blind hole 4 is formed upward at the lower surface. Is basically almost the same as the conventional example.

However, as shown in FIG. 2, a plurality of notched grooves 12 having a V-shaped cross-section are formed radially on the outer peripheral side of the annular groove 3 in a radial arrangement therefrom. That is, as shown in FIG. 3, the annular groove 3 is formed in a U-shaped cross section, and approximately in the middle of the outer peripheral side wall (the engagement groove portion 6).
8 (C)), the notched groove 12 has a V-shaped cross section with a constant angle θ (see FIG. 4) in a radially outward arrangement from FIG. It inclines so that it becomes shallow outward in the direction, and penetrates while converging the outer peripheral edge.

The number of the cutout grooves 12 is preferably 4 to 8 so that the non-insertion portion 7 is easily deformed even when the thickness of the non-insertion portion 7 is increased, but is not limited to the number. A substantially triangular solid portion 13 is formed between the radially arranged cutout grooves 12. The top portion R of the solid portion 13 facing the annular groove 3 is rounded and chamfered, but the chamfering is not necessarily required. By making the boss portion 5 have a conical shape without a top portion (a truncated cone shape), the amount of movement of the solid portion 13 to the boss portion 5 can be adjusted and set.

The engagement groove 6 is formed to be larger than the thickness of the floor plate 9, and the rib 7 a is formed so that the outer peripheral edge of the non-insertion portion 7 is pressed against the upper surface of the floor plate 9. The rib portion 2a of the insertion portion 2 is pressed against the lower surface of the plate 9.
Is formed. Further, the blind hole 4 is formed in the insertion portion 2 with an opening larger than the maximum diameter of the boss portion 5 and a hole bottom as compared with that of the conventional example.

Therefore, when mounting the grommet 11 in the hole 10, as shown in FIG. 3, the insertion portion 2 is applied to the inner peripheral edge of the hole 10, and the upper surface of the boss portion 5 is pushed with a fingertip or a stick. As shown in FIGS. 5 and 6, the solid portion 13 crushes the cutout groove 12 (see arrow), the grommet 11 converges toward the center, the non-insertion portion 7 is reduced in diameter, and the solid portion 13 is reduced. Abuts on the outer peripheral surface of the boss 5.

In this state, the outer diameter of the insertion portion 2 near the rib portion 2a is substantially equal to the inner diameter of the hole 10, the inner peripheral edge of the hole 10 is fitted into the engagement groove 6, and the non-insertion on the rib portion 7a side is not performed. The part 7 contacts the floor plate 9 and prevents further movement. The annularly formed ribs 2a, 7a contact the floor plate 9 to improve the sealing performance.

At this time, even if the force for pushing the upper surface of the boss portion 5 is further increased, the top portion R of the solid portion 13 is in contact with the boss portion 5, and both are solid and cannot be deformed. In addition, the non-insertion portion 7 does not decrease in diameter smaller than the inner diameter of the hole 10, and therefore does not penetrate the hole 10.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A proper grommet 11 according to the present invention
In detail, the relationship of each part to obtain is as follows. In FIG. 8A, a ≒ b (where a ≦ b), a <c, a: lap allowance,
b: flex space for a, d: rib, e: tapered surface.
The width of the cutout groove 12 is determined by the diameter reduction amount (# 2a). The depth of the cutout groove 12 on the outer peripheral side is determined by the groove width and the number of grooves.
In FIG. 8B, h <i, j: bending fulcrum. Further, in FIG. 8C, the height m at the k-point and the l-point is assumed to be the same (k, l = m) in order to secure rigidity.

[0020]

According to the present invention described above, the cutout groove is formed integrally with the annular groove in the radial direction on the outer peripheral side of the annular groove surrounding the boss on the upper surface of the grommet, so that it is fitted into the hole of the floor plate. When the boss is pushed into the boss, the notch grooves are radially arranged, so that the upper surface of the grommet is reduced in diameter in a well-balanced manner, and all the solid parts partitioned by the notch grooves crush the annular groove and hit the boss. The rigidity is increased by contact, and the non-insertion portion is prevented from being deformed smaller than the inner diameter of the hole, so that the inconvenience of the grommet protruding from the hole by receiving a strong pushing force can be structurally solved.

Further, since the cutout groove is a groove having a V-shaped cross section, the upper surface of the grommet is easily deformed, so that the thickness of the non-insertion portion can be increased, Since the rib portion is formed annularly on the non-insertion portion side, sealing performance with a floor plate or the like is improved, and furthermore, the boss portion has a truncated cone shape to adjust the amount of movement due to deformation of the solid portion. Thus, a grommet that can be easily mounted can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view of the grommet according to the present invention.

FIG. 3 is a sectional view taken along line SA-SA of FIG. 2;

FIG. 4 is a sectional view taken along line SB-SB of FIG. 2;

FIG. 5 is a plan view of a grommet showing an operation at the time of mounting.

FIG. 6 is a vertical cross-sectional view of the grommet at the time of mounting.

FIG. 7 is a cross-sectional view showing the deformation of the cutout groove at the time of mounting.

FIGS. 8 (A), (B) and (C) are explanatory views showing the relationship among the respective parts for obtaining an appropriate grommet according to the present invention.

FIG. 9A is a plan view showing a conventional grommet and FIG.
It is -SC sectional drawing (B).

FIGS. 10A, 10B and 10C are longitudinal sectional views showing a mounting process of a conventional grommet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... Insertion part 2a ... Rib part 3 ... Annular groove 4 ... Blind hole 5 ... Boss part 6 ... Engagement groove part 7 ... Non-insertion part 7a ... Rib part 9 ... Floor plate 10 ... Hole 11 ... Grommet 12 ... Notch opening groove 13 … Solid part

Claims (5)

[Claims] 1. A grommet having an annular groove extending toward a lower surface in an upper circumferential portion and a boss portion formed in a central portion, the grommet being circumferentially equidistant on the outer circumferential side of the annular groove in the upper circumferential portion. A grommet, characterized in that a plurality of notched grooves are formed integrally with the annular groove in the radial direction. 2. An annular groove extending toward the lower surface in a circumferential portion of an upper surface, a boss portion is formed in a central portion, and a flange-shaped non-insertion portion is formed outside the annular groove. An annular engagement groove for engaging the inner peripheral edge of the hole to be closed is formed below, and a truncated cone-shaped insertion portion is formed below the engagement groove,
A blind hole extending toward the upper surface is formed at the center of the lower surface. The blind hole is formed in a conical shape having a large diameter at the opening end and a small diameter toward the bottom of the hole, and an annular groove at the circumferential portion of the upper surface. A grommet characterized in that a plurality of notched grooves are formed integrally with the annular groove in the radial direction at equal intervals in the circumferential direction on the outer peripheral side of the grommet. 3. The grommet according to claim 1, wherein the notched groove is a groove having a V-shaped cross section. 4. The grommet according to claim 1, wherein a rib portion is formed in an annular shape on an insertion portion side and / or a non-insertion portion side of the engagement groove portion. 5. The grommet according to claim 1, wherein the boss has a truncated cone shape.